1. Field of Invention
The present invention relates to a toaster, and more particularly to a toaster with a motor-driven rack which is capable of precisely and efficiently lowering a bread slice into the toaster for toasting, and raising the bread slice when the toasting is finished.
2. Description of Related Arts
Toasters have long been developed and widely utilized for making a regular bread slice brown and crisp to become a toast. Such a toast is warmly welcomed by people of all ages and therefore served in a wide variety of restaurants and groceries.
A conventional toaster comprises an toaster case having a toaster slot for receiving a bread slice therein, a toasting device disposed in the toaster case for toasting the bread slice in the toaster slot, and a rack frame which is adapted to support the bread slice therein for toasting, and is movably supported in the toaster slot in such a manner that it is capable of moving between a lower toasting position and an upper operative position, wherein in the lower toasting position, the toasting rack is lowered to activate the toasting device for toasting the bread slice in the toasting rack, wherein in the upper operative position, the toasting rack is raised for manual retrieval of the toasted bread slice.
The conventional toaster further comprises means for raising the toasting rack from the lower toasting position to the upper operative position. The raising means usually comprises a resilient element, such as a compressive spring, mounted in the toaster case and arranged to normally apply an upward urging force to the toasting rack in such a manner that when toasting of the bread slice in the toasting position is finished, the resilient element is arranged to apply an upwards force to the toasting rack for raising it from the lower toasting position back to the upper operative position.
Despite its popularity, it is obvious that such a conventional toaster has several discrepancies. First of all, the resilient element is only designed for a particular bread's slice size and shape, or at best for a limited range of bread slice's sizes and shapes. That means the conventional toaster is not suitable for all kinds of bread slice, even though their sizes can be fitted into the toaster slot. As a result, when the force provided by resilient element is too small, the bread slice, when toasted, will still stay in the toaster slot so that a user cannot take the toast out from the toaster (under-ejecting). At worst, the bread slice may be burnt and cause fire. When the force is too large, the toast may be ejected into the air (over-ejecting) from the toaster and get dirty when falling onto the ground. As result, the bread slice is wasted and the user needs to take some time to make another one. But the most anomalous thing is that the second bread slice usually comes from the same batch as the first slice, therefore, the second bread slice risks the scenario as that of the first slice.
Second, when the resilient element has too large a stiffness, not every user of the toaster can be able to depress the toasting rack to the lower toasting position in order to toast. In this context, it is kind of dangerous especially for a child who wants to do the toasting by himself/herself.
Of course, precise raising and lowering of the toasting rack can be accomplished by electrical and electronic methods. However, this inevitably increase the manufacturing and the ultimate selling price of the toasters. As toasters have become a very popular kind of domestic small appliances, generally speaking, their price are affordable by most of the families, and as a result, the above-discrepancies of the conventional toasters should not be overcome at the expense of increase in manufacturing and selling price thereof. Otherwise, public interest would actually be jeopardized by inventing something new and expensive, yet it is supposed to be an affordable and convenient product.